Today I did a little search to find out what pollen the bees outside on our lavender are carrying. So, that may seem rather stupid, but it's not necessarily all lavender - most of them have bright orange pollen, but some have yellow.
In the process I discovered this delightful little blog entry discussing exactly that topic - it contains some useful links to online resources for pollen matching.
Lavender pollen, as it happens is bright yellow - so the second bee above may be collecting lavender pollen, the bright orange isn't. I have a suspicion that the orange is actually asparagus, as we are located very much in farming region and surrounded by fields outside of the town. Indeed, the nearest field is broad-bean, so there could easily be something like asparagus nearby; and theasparagus crop was said to be early and good this year due to the unusually warm spring.
Check out the electron microscope pictures of pollen - they are amazing!